Low resistance air filter device

ABSTRACT

A low resistance air filter device comprises a tubular case ( 2 ) for at least a filtering element ( 3 ) fixed to a lower opening ( 9 ) of the case ( 2 ). This latter case is provided, at its opposite upper opening ( 10 ), of outlet means ( 8 ) provided with an outflow opening ( 7 ) for the air. The outlet means ( 8 ), at the outflow opening ( 7 ), are provided of a tubular body protruding toward inside said tubular case ( 2 ) and connect in flow communication the inside volume of the tubular case with the outflow opening ( 7 ) the same.

TECHNICAL FIELD

The present invention relates to the technical field concerning filterdevices of the air destined to the air-fuel mixture sucked by thecombustion engines and refers to a low resistance air filter device.

The known filter devices comprise an air filter, having a formflattened, cylindrical or conic, contained in a respective case havingan opening in flow communication with the air intakes and a furtheropening connected to the engine.

BACKGROUND ART

Are known cases whose opening connected to the engine, and thereforedownstream of the filter in comparison to the air flow, it introducesstrong resistances and turbulences that cause the drawback to reduce theair flow to the engine.

Are known cases for filters provided with an inner link between theinlet opening and the side wall fit to reduce the air resistance.

A drawback of such filtering devices consists in that the link allowsthe passage of possible extraneous object, for instance nuts or screwforgotten or fallen in the case of the filter, in the inlet collectorsof the engine with serious damage risks of this latter. The risk ofextraneous object presence is particularly relevant in the race filterdevices that are continuously opened for inspections, cleaning,substitution also during hurried phases of job on different organs ofthe engine in the same time.

Further drawbacks of the said known filters consist in the fact thatthey increases the weight and they reduces the inside volume for theair.

DISCLOSURE OF THE INVENTION

A purpose of the present invention is to propose an air filter devicehaving low resistance and able to stop possible extraneous object, alsoof big dimensions, in the case.

Further purpose of the present invention is to propose a device toreduce the air resistance without reducing the useful volume of thedevice and without getting heavy it.

Other purpose is to propose a device can be easily housed in the engineroom.

The above mentioned objects are achieved according to the content of theclaims.

BRIEF DESCRIPTION OF THE DRAWINGS

The characteristics of the present invention are underlined in thefollowing with particular reference to the enclosed drawings, in which:

FIG. 1 shows a schematic longitudinal section view of the device of thepresent invention;

FIG. 2 shows a longitudinally sectioned view sectioned by a longitudinalplan perpendicular to the one sectioning FIG. 1;

FIG. 3 shows a top view of the FIG. 1 device.

BEST MODE OF CARRYING OUT THE INVENTION

With reference to FIGS. 1-3, 1 indicates a low resistance filter devicefor the feeding of combustion engines mainly including a tubular case 2,a filtering element 3, support means 4 and a outlet means 8.

The tubular case 2 has an elliptic or oval section and it is providedwith an lower opening 9 and an upper 10. Furthermore the tubular case ispreferably made of carbon fiber so that it releases a thermal insulatorbetween the external environment and the air crossing it. The tubularcase 2 is fixed to the support means 4 by fixing means 14 consisting ofscrew or of fastener.

The outlet means 8 are constrained to a upper opening 10 of the tubularcase 2 and they are centrally provided of an outflow opening 7 incorrespondence of which they present a tubular body 11 protruding towardinside of said tubular case 2. Such tubular body 11 connects, in flowcommunication, the inside volume of the tubular case 2 with the outflowopening 7 the same.

The form of outlet means 8 is similar to shaped flange integral with thetubular body 11 being shaped as the trumpet outlet.

Preferably the trumpet of the tubular body 11 expands, or enlarges,toward inside of the device 1. In alternative, the invention providesthat the tubular body 11 is narrowed, or is restricted, toward inside ofthe device 1 assuming a truncated ogive shape.

The outlet means 8 are peripherally provided of a recess 14 for thehousing of the inside wall of the tubular case 2 in its upper opening10. The outlet means 8 are detachably fixed to the tubular case 2 bymeans of screw or fastener fixing means 15.

The device includes support means 4 fixed at the lower opening 9 of thecase 2 and fit to constrain the filtering element 3 at one inlet opening5 for the air of the support means 4 the same.

The support means 4 are discoid shaped and centrally provided of theinlet opening 5 linkable to the air intakes of the vehicle. An innerthroat of the support means 4 houses an end of the filtering element 3that can be fixed integral with the support means 4, for instance bymeans of adhesive or plastic material melting. In alternative the end ofthe filter can be detachably housed in a respective throat, annular seatshaped, of the support means 4.

The support means 4 are peripherally provided of a seat 13 for housingthe inner wall of the tubular case 2 at the lower opening 9. They aremade of nylon strengthened with glass fiber.

The filtering element 3 has cylindrical form and is made of cottonsoaked with low viscosity oil. It is internally provided of airdeflecting means 6, connected to the free end of the filtering element 3in such way that the air flow entering from the opening 5, and pointedout by the arrows F of FIG. 1, it is forcedly deflected by thedeflecting means 6 toward the filtering element 3. The deflected airflow crosses the filtering element 3, it crosses the interspace formedby this latter and the external case 2 and it exits, through the tubularbody 11, out the outflow opening 7 entering inside air ducts indirection of the engine.

The deflecting means 6 are substantially shaped as a cone whose vertexis directed toward the inlet opening 5 and whose base is integral fixedto the free edge of the filtering element 2. In alternative it isprovided that the free edge of the filtering element 2 detachablymatches the base of the deflecting means 6. The substantially conicshape of the deflecting means 6 can have a concave profile 6 a or convex6 b for instance of parabolic kind. More in detail, said almost conicshape of said deflecting means 6 has an axial section shaped as twohalf-parabolas with parallel axes and joined branches at the vertex ofthe deflecting means 6 making the concave 6 a or the convex 6 b profile.

The device includes spacer means 20, for instance made of plastics andof prismatic form, interposed between the tubular body 11 and thefiltering element 3 and matching the inner wall of the tubular case 2for the centering and stopping of the filtering element 3.

The operation of the device provides that the recess between the tubularbody 11 and the inside wall of the tubular case 2 form a sort of trapfit to prevent or to reduce the risk of the passage, toward the engine,of extraneous objects as nuts, screws, washer, split pin and the like.The conformation of the tubular body 11 provides a low resistance andlow dynamic losses of air flow feeding the engine without heaviness andwithout reducing the inside volume of the device in a remarkable manner.

An advantage of the present invention is to propose an air filter devicehaving low resistance able to stop extraneous object, also having bigdimensions, inside the case downstream filter without reducing theuseful volume of the device and without getting heavy it.

Other advantage is to propose a device can be easily housed in theengine room trough its oval or elliptic section shape.

1. Low resistance air filter device comprising a tubular case (2) for atleast a filtering element (3) fixed to a lower opening (9) of the case(2) said device being provided, at its opposite upper opening (10), ofoutlet means (8) provided with an outflow opening (7) for the air, saiddevice (1) being characterized in that the outlet means (8), at theoutflow opening (7) are provided with a tubular body (11) protrudingtoward inside of said tubular case (2) and connecting, in flowcommunication, the inner volume of the tubular case with the outflowopening (7) the same.
 2. Device according to claim 1 characterized inthat the outlet means (8) are formed as a shaped flange integral withthe tubular body (11).
 3. Device according to claim 1 characterized inthat the tubular body (11) is trumpet shaped.
 4. Device according toclaim 3 characterized in that the trumpet of the tubular body (11)enlarges toward inside of the device (1).
 5. Device according to claim 3characterized in that the trumpet of the tubular body (11) is narrowedtoward inside the device (1).
 6. Device according to claim 1characterized in that it comprises support means (4) fixed at the loweropening (9) of the case (2) and fit to bind at one inlet opening (5) forthe air of the support means (4) the same, said filtering element (3).7. Device according to claim 1 characterized in that the free end of thefiltering element (3) it is inside provided with deflecting means (6) ofthe air.
 8. Device according to claim 1 characterized in that saysoutlet means (8) are peripherally provided of a recess (14) for housingthe inside wall of said tubular case (2) at its upper opening (10). 9.Device according to claim 1 characterized in that says outlet means (8)are detachably fixed to said tubular case (2) by means of fixing means(15).
 10. Device according to claim 7 characterized in that saysdeflecting means (6) are substantially shaped as a cone whose vertex isdirected toward the inlet opening (5) and whose base is integral fixedto the free edge of the filtering element
 2. 11. Device according toclaim 10 substantially characterized in that said almost conic shape ofsaid deflecting means (6) has an axial section shaped as twohalf-parabolas with parallel axes and joined branches at the vertex ofthe deflecting means (6) making a concave (6 a) or convex (6 b) profile.12. Device according to claim 1 characterized in that says tubular case(2) has an elliptic or oval section.
 13. Device according to claim 1characterized in that says tubular case (2) is made of carbon fiber. 14.Device according to claim 1 characterized in that says filtering element(3) it is in cotton soaked with low viscosity oil.
 15. Device accordingto claim 1 characterized in that said support means (4) are peripherallyprovided of a seat (13) for housing the inside wall of said tubular case(2) at its lower opening (9).
 16. Device according to claim 1characterized in that said tubular case (2) is detachably stopped tosaid support means (4) through fixing means (14).
 17. Device accordingto claim 1 characterized in that said support means (4) are made out ofnylon strengthened with glass fiber.
 18. Device according to claim 1characterized in that says filtering element (3) is cylindrical. 19.Device according to claim 1 characterized in that it includes spacermeans (20) positioned between the tubular body (11) and the filteringelement (3).
 20. Device according to claim 19 characterized in that thespacer means (20) matches the inside wall of the tubular case (2).